Learn: VSEPR Notation | Quizlet

A

the number of central atoms

X

the number of terminal atoms

E

lone pairs of valence electrons around the central atom

AX2

ideal: linear, observed: linear

AX2E

ideal: triagonal planar, observed: angular/bent

AB2E2

ideal: tetrahedral, observed: angular/bent

AB2E3

ideal: trigonal bipyramidal, observed: linear

AB3

ideal: trigonal planar, observed: trigonal planar

AB3E

ideal: tetrahedral, observed: trigonal pyramidal

AB3E2

ideal: trigonal bipyramidal, observed: t-shaped

AB4

ideal: tetrahedral, observed: tetrahedral

AB4E

ideal: trigonal bipyramidal, observed: irregular tetrahedral (see-saw)

AB4E2

ideal: octahedral, observed: square planar

AB5

ideal: trigonal bipyramidal, observed: trigonal bipyramidal

AB5E

ideal: octahedral, observed: square pyramidal

AB6

ideal: octahedral, observed: octahedral

ideal geometry

electron domain geometry

observed geometry

molecular/actual geometry

steric number

number of atoms bonded to central atom + number of lone pairs on central atom

steric number shapes

Steric Number 2: Linear shape, Steric Number 3: Trigonal planar shape, Steric Number 4: Tetrahedral shape, Steric Number 5: Trigonal bipyramidal shape, Steric Number 6: Octahedral shape